It may also help to have some understanding of the term "24k". This refers to printed paper maps where the scale is 1:24000. In other words, one inch on the map equals 24,000 inches (2,000 feet) in the real world. A 100k map would be 1:100,000 or 1 inch equals 100,000 inches (a little over 1.5 miles). As you can see, a 24k map would be much more accurate than a 100k.

In the digital world, this gets a little murkier because we are looking at the maps on a video screen where we can zoom in and out, instead of printed paper at a fixed scale. And there is no standard for how many pixels per inch on video screens.

But 24 x 4 is roughly equal to 100, so that would imply a 24k map has 4x the amount of detail. But really, it's much more because maps have width x height and we need to compare the area which is a squared function. So it would actually be 4 squared (4x4=16). In theory, a 24k map is capable of representing 16x the detail of a 100k map.

With satellite imagery, we think in terms of how many feet (or meters) is represented by each pixel on your screen. Garmin's Birdseye imagery is about 2 feet per pixel. This is way more detail than a 24k map has. I have made my own raster based maps from USGS 24k maps, and found that 10 feet per pixel was required to clearly see all the detail. So to compare Birdseye to a 24k map, the calculation would 10 ft per pixel / 2 ft per pixel = 5 ^2 = 25.

Therefore, assuming a nice clear photo, Birdseye can provide 25x the amount of detail as a 24k map. We could nitpick about some of these numbers, but this should give you some feeling for the relative usefulness of maps vs aerial imagery.